Oops, it doesn't look like 'dunk over a teacher day' is a national day..

Other days

gum

Gum Day
ormille

Ormille Day
bow tie

Bow Tie Day
cat girl

Cat Girl Day
stud

Stud Day
aloxolt

Aloxolt Day
self care

Self Care Day
my little pony

My Little Pony Day
pampering

Pampering Day
gallery

Gallery Day